Question 2

The electrostatic force on a small sphere of charge 0.4 μC due to another small sphere of charge − 0.8 μC in air is 0.2 N.

(a) What is the distance between the two spheres?

(b) What is the force on the second sphere due to the first?

Answer

** (a) **Electrostatic force on the first sphere, *F* = 0.2 N

Charge on this sphere, *q*_{1} = 0.4 μC = 0.4 × 10^{−6 }C

Charge on the second sphere, *q*_{2 }= − 0.8 μC = − 0.8 × 10^{−6 }C

Electrostatic force between the spheres is given by the relation,

Where, ∈_{0} = Permittivity of free space

The distance between the two spheres is 0.12 m.

**(b) **Both the spheres attract each other with the same force. Therefore, the force on the second sphere due to the first is 0.2 N.

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krish
2019-12-10 22:09:18

this is very useful to me thanks for this

Ankur mishra
2019-08-22 13:41:20

Very nice

Lalisa
2019-08-19 21:12:54

Very helpful

Amit
2019-04-30 15:04:22

Helpful but u haven't given the reason that why u put 8 instead of .8

Swati joshi
2019-04-26 21:03:33

It's really very helpful

Minjae
2019-04-24 09:18:13

Ha! Thanks for this so simple it was and 0.8 or 8 no problem take 9.0 if u use o.8 or vice versa

Anmol
2019-04-10 13:49:59

Why taking 8 instead of .8

Kaamil
2019-03-27 17:43:12

Very good n thank you for help

Minal
2019-03-17 08:31:37

Why taking 8c instead of 0.8

Minal
2019-03-17 08:30:24

Why taking 8C insead of 0.8 C and why not 4C instead 0.4C.

- NCERT Chapter

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